Embodiments of the present invention relate in general to the field of X-Ray detection, and more specifically to a collimator of X-Ray device, wherein the collimator uses a LED lamp to indicate the X-Ray field.
The current classical collimator is designed to have a halogen lamp with reflection to produce a light field to indicate an X-Ray field. This design has at least the following disadvantages.
First, the halogen lamp has a short life. Under normal usage, with the best halogen lamp for the collimator of a X-Ray device, such as a Mammo (mammography) radiography device, it will burn out at 3 years at most, which requires field engineers to periodically replace the lamp. This brings in service cost and decreases customer satisfaction.
Second, the halogen lamp is quite hot. To produce enough brightness, high energy is needed, and heat is generated with high power. This makes the lamp hot, and the temperature is about 150° C. The heat also brings in air flow. The air flow brings in dust which makes the collimator dirty and the light brightness decreases as the dust increases.
Third, the halogen lamp is expensive. A Halogen lamp is mainly structured by a halogen bulb, DC module and mechanical parts which increases maintenance/repair and component replacement costs.
Fourth, the halogen lamp with reflection cannot produce an X-Ray field with high brightness uniformity. The reflection part, shaped similar to a round cup with a hole at the cup bottom, cannot cover complete half ball around the halogen lamp. This makes a black zone in the center of the light field. To make up this non-uniformity, a diffuser is added before the lamp.
Lastly, the halogen bulb in the lamp product consistency is poor. The filament position sometimes deviates from the center, and this is a product defect distinct of the halogen lamp that cannot change. This character brings a high material defect rate to the production team.